Scoty

After trying loads of different gaskets which have failed to seal the up-pipe - headers flange, I was given some of this stuff to try.

FLEXICARB GRAPHITE SEALING MATERIAL

Flexicarb is a pure exfoliated graphite material exhibiting excellent sealing characteristics, withstanding a wide range of temperatures, pressures and chemicals.
This homogeneous material is free of respirable fibers, binders and additives. Standard grades are 95% to 98% pure, with a nuclear grade available at 99.9% purity.
Flexicarb is extremely conformable giving it the ability to flow into flange surface imperfections. Its low permeability and chemical resistance make it an ideal choice as a sealing material.
The high purity of Flexicarb is chemically inert to most media. (Note its limitations on oxidizing compounds.)
Flexicarb covers a wide temperature spectrum, from cryogenics through elevated temperatures. It can be supplied with an inorganic passivating inhibitor to increase its oxidation and corrosion resistance. Recent experiences and tests have shown that Flexicarb will oxidize over time. Care should be taken when considering the use of Flexicarb foil for applications above 330°C (650°F).

Flexicarb ST
Flexicarb tanged steel reinforced graphite is a laminate sheet material of graphite foil layers mechanically bonded to a 0.1 mm (0.004”) thick 316 stainless steel tanged core. The core enhances the mechanical strength of the graphite foil. Flexicarb ST is suitable for sealing steam, water, gasses, hydrocarbons, alkalis and chemicals. It is not recommended for use on glass-lined, bronze or aluminum flanges.


Flexicarb SR
Flexicarb steel reinforced (SR) is a high performance laminate comprising of graphite foil chemically bonded to each face of a 0.05mm (0.002”) 316 stainless steel substrate. SR possesses good mechanical properties and is suitable for sealing steam, water, gases, oils, hydrocarbons, alkalis.


Flexicarb WR
Flexicarb wire reinforced is a graphite sheet with a 316 stainless steel woven wire mesh. Flexicarb WR is suitable for low pressure applications.


Flexicarb NR
Flexicarb NR is a graphite laminate consisting of graphite foil with a nickel core 13 microns (0.005”) thick. The bonding agent is a high temperature, chemical resistant nitrile phenolic adhesive.


Temperature Range for Flexicarb Material
Cryogenics to 700°C (1292°F) ia an inert or reducing atmosphere. Cryogenics to 400°C (750°F) in and oxidizing atmosphere.*


Pressure Range for Flexicarb Material
Recommended for Class 150 and 300 applications for all above except Flexicarb WR which is recommended for Class 150 only.

Not entirely sure which material of the 3 it is, it's only marker Flexicarb.
It's extreemly easy to work with and a gasket can be made up in a matter of minutes.
It's sealed the flanges no problem (10mm gap to begin with) but my main concern is the working temps, any ideas ifit will withstand the head of the headers?

AlanG

Sounds a bit like steam jointing...

10mm gap? A bit excessive is it not?

Scoty

Just found out the stuff I have will start to oxidise at 320 deg C, so it's not going to work either.
Good news is the company who manufacture the material have offered me another material called Thermiculite.

It's a high temperature sheet gasket comprised of chemically and thermally exfoliated vermiculite on a tanged 0.1mm (0.004”) thick 316 stainless steel core.
It's proven at 970 'C with an upper limit of 1050 'C and has a thickness range of 1/32 to 1/8.

Scoty

Fitted the Thermiculite gasket, so it's a case of wait and see if it can withstand the heat etc.

The peice I got is 3mm thick so it takes a bit of the strain out of the up-pipe when the flanges are tightened up, and it's very conformable.

AndrewC

Keep us posted.

I used some dodgy plastic encapsulated crystaline asbestos something or other gaskets from the US when I fitted my solid uppipe, hasn't leaked for about 9months. Now I'm going to fit some tubular headers and they are no longer available, something like this might me a suitable alternative.

Andrew...

Mr J

Alan what gasket did you use on with your Gruppe-s mainfold ?
thinking of fining the leak I have on my set now.

Jan